Improvement in the process and apparatus for treating wood



.pero et in..

lRAlilAYFOR'D, 0F BOSTO, MASSACHUSETTS.

Leiters Patent No. 101,012, dated MarchA 22, 1870.

IMPROVEMENT IN THE PROCESS AND APPARATUS POR TREATING- WOOD.

The Schedule referred to in these Letters Patent and making part of the lame .To al? to whom there prescrits shall come:

Be it. known that I, IRA Harmen, of Boston, in the county of Suffolk and Slate of Massachusetts, have made an invention of a new and use'tnl Process l'or Treating Wood, in order to'prescrve as well as to improve the appearance of the same; and do hereby declare the following to bea full, clear, and exact description thereof, due reference ,being had to the 4accompanying drawings making part of this specification, in wliichlrigure l is a perspective representa-tion';

'Figure 2, a like view; and

j Figure 3, a longitudinal section;

l`igure'4,'a vertical section through the cistern and retort,as well as thev steam-generator; while Figure 5 is a horizontal section, taken longitudin- 'arly ofthe said retort.

ln `the drawingsl A denotes a steam-generator, of any well-known or desirable construction, while alongside of this generator isdsposed a' horizontal cylindrical retort, B, this retort being composed ot' metal, Vsuiciently strong to withstand an `internal pressure of from one to twov hpndred .pounds persquare inch, and being provided with a door, at', formed of such metal and so applied to the retort as to be capable, when seemed in place,

`oi' sustaining a pressure equal'to that of the body of the said retort.

ln close proximity to the retort .B will be seen 'at C an upright cistern cr tank, this cistern being cornposed ot` material and possessing" strength similar' to that of the retort B, since it is subjected to the same pressure, a cover, b',.being applied to it, which, when the apparatus is in operation, is to be securyely bolted andconh'ned in place.

D denote'sa steam-conduit leading from the generator A, such conduit being conducted into' t-lre retort B,

and caused to traverse its greater area in an irregular or serpentine direction, the interior of this conduit creating a. large radiating surface, in order to maintain a high temperature within the retort.

Thel conduit D after circulating throughout the retort B is returned to the outside of'the saure, and thence carried into and compelled to course about the interior ot' thc cistern (l, and then effect its exit at the opposite extremity of said cistern, the purpose of thus carrying the steam-conduit about theA interior of the cistern being to heat its contents, Aand maintain them in astute of liquetaction.

After leaving 'the cisteru C, thc condnitis made to enter the upper part ot' thel retort B, in order to convcy steam mto the same.

As it enters the interior ofthe retort B, the conduit I) makes partof or is prolonged into a second irregular or serpentine pipe, D, this pipe D being tirstcarried to and spreading over the lower portion of the retort above the conduit D, thence upward to and Aexpanding over the upper portionl of theinner area of such retort, the lower surfaces ofthe upper portions of the pipe D' boing tbrarninous or pierced'with numerous small holes, in orderthat the preservative agents hereinafter referred to be contained in such pipe may descend ina shower or spray upon and envelop the wood placed in the retort, it being understood that the extreme termination of the showering-pipe D is within the retort.

Between the cisteru C and the retort B the conduit D is provided with a blow-oil' pipe, shown at c in the. drawings, this blow-oft' pipe being furnished with a cock, h.

1n addition to this blow-01T pipe c, the conduit D is formed with a branch or oset, j, which leads into the cistern ,'C,`and serves under certain conditions to admit steam directly into the interior of the same.

In addition to the conduit D, which joins or unites with the upper partv of the showering-pipe D', within the retort B, a second and short pipe or conductor, E,

connects the lower extremity of the pipe Dwith the interior of the cistern O, a cock, k, being placed in 'this pipe, as' shown in the drawings.

A cock,'o', is placed in the conduit D immediately after-,its exit from the retort B, while a third cock, h, is also placed in the conduit D, immediately before its entrance. into the cistern C.

A cock, i, is placed in the branch or offset j of thev conduit D.

1u addition to the various pipes hereinbefore enumerated, a return feed-pipe, g, effects free communication, when its cock, Ishown at f in' the drawings, is opcn,lbetween the bottom ot' the retort B and that ot the cistern O, this feed-pipe-g being formed-with a blow-oit` branch, e, which in turn is turned with a cock, d.

The generator A is for'the purpose of lgenerating steam which is used in the apparatus, as hereinafter explained.

The retort B is to cont-ain the wood to be treated while'undergoing the process of beingstcamed, as it is generally called, and of receiving its charge of for- 'eign substances with which'it is to be impregnated.l

The cistern C, as before stated, is to contain' the chemical agents or oth er materials with which the wood is to be impregnated,` whether dead oils, so-called in' some oi' their' varieties or products, parafiine, paln1-oil, or other olcaginons matters, or any desirable substances.

I am aware thatmany and various processes are in existence for preserving wood from decay, and from changes ot' conditions in its bulk by the action of the atmosphere, as well as to improve its texture and appearance.

So t'ar as my knowledge extends, however, no means stances.

has heretofore been originated lfor varying and regulating thc amount of material to be injected into the p ores of the wood, and assomc of the substances now employed in treating wood are expensive, and in view of the fact that wood will absorb twice its own weight of such substances, the value of my invention becomes apparent uhc'n lhe fact is understood that this proportion of preservative agents is greatlyfinexccss of what is necessary, or even desirable, and only adds to the expense ofthe process.

With this knowledge, my invention may be said to consist chieiiy in.providiug a means of varying and regulating the quantity of materials admitted to the retort, and consequently injected into the wood, al-

' though my invention possesses other characteristics 4and novel features which enhance its value.

lhe employment oi' an auxiliary or independent cistern or receptacle, into which the preserving agent is placed previous to its entrance to the retort, enables me to charge the wood with the quantity desired, in order to accommodate the wishes or necessities of the owners of the lumber.

Hence, should such parties desire a certain amount of lumber charged with a given quantity of preserving material, m'y process enables me to' effectsnch object. As this quantity of material varies `considerably in different instances, I am enabled to regulate the expense of the preparation of the wood to suit circum- Having thus described the mechanical c( ustruction of the apparatus in 'which I carry out my present invention, as well as explained the nature and purposes of such invention, or the process which embodies such invention, I will now refer to the mode of treatment of wood as carried on in pursuance of the object herein'stated, prefacing such explanation by the remark that, uponstarting with the process, the cocks a h o' hereinbefore mentioned are opened, and the cocks d, f, t', k, and b closed. f

Steam is generated in the boiler A. The wood in the determined quantity is to be deposited within the retort B upo`n racks suitably disposed therein, or upon a car which is trundled into such tank, while the Tequisite and predetermined quantity of preservative material, with which such wood is to be charged, is placed within the cistern or receiver C, the door of the generator B as .well as the cover of the cistern being securely fixed iu place, thus 'tightly` sealing their coutents.V

Steam from the generator A passes into and -through the conduit D and into the retort B, such steam, in its transit through this tortuons channel, heat-ing and liquefying the contents of the cistern C, as well as permeating and expanding the pores and cellular structure of the wood, andexpelling therefromfthe moisture or sap and gases, and coagulating the albunien, the ensuing evaporation, condensation, and esc-ape'ot' the apors within, and from the' pores and cells,` leaving the wood in a porous and -soft state, highly favorable to receive and absorb t-he preserving agents.

This preparatory treatment of the Wood having been eected, the cock a ot". the conduit D is closed, and the cock b of its blow-off or exhaust-pipe c opened,

the steam, by this means heilig shut ofi' from entering directly the retort B, and allowed to escape into the atmosphere, or otherwise utilized, the object in continuing this circulation of steam being to maintain the temperature of the cistern C, and the liquefaction of the.conteuts`. 1 y

Simultaneous with the act of closing the cock a beruraux' fore mentioned as shutting oi direct supply ol stem-i to the retort B, the. cock d ot' the escape-pipe c is opened to permit of exit of-vapor, coiulcnscd water, impurities from the woodJ tbc., li'oni such retort, and create a vacuum therein, the cock f of the feed or rlturn-pipe y, of whichy the pipe c is a branch, being at this time and previously closed.

After the escape from thc retort of excess oi' steam, condensed watcrsap, and impurities from the wood, as explained, the cock rl is to be tightly` closed, thus perfecting and maintaining the desired vacuum, or partial vacuity oft-hc retort B.

rIhc cork d having been closed as explained, and

the requisite vacuum obtained within the retort, they' cocks hand b ot" the conduit` 1) are closed, and the cock -i of thc branch or otfsetj, which up to this time has remained closed, as well as the cock k of thc 4connecting-pipe E, which has also been closed, are opened, thus permit-ting steam from the generator lA to pass directly under pressure into the cistcru (l, and drive from it the preservative or othersubstances contained therein these 'contents being forced into and through the meandering showering-pipe D', and from thence precipitated upon and about the wood below, and into the pores and cells of which they enter.

The excess ofthesc last-mentioned substances above what are absorbed at firstby the wood, falls to the bottom of the retort.

The proper time having elapsed' for this first act of charging thewood to be consummated, the cockfiofthe oiset pipe j, before mentioned, is closed, or returned to its original position, and the cock f of the return yfeed-pipe g opened for the first time, the cocks h and a being also openedas originally stated, and the cocks 'b and k closed-as at the starting lpoint of this explanation.

,These last-mentioned positions of the varibus cocks allow the steam from the generator A to enter the retort B, and derive tiom it the preservative agents .or impregna-ting substances which have accumulated upon its'bottom, through or by means of the returnl pipe g back into the cistern O, where they collect in readiness to renew their journey to the retort, as at iirst explained, which brings us-to our starting point.

This entrance to and discharge from the ret-oit of the impregna-ting agents is to be continued until the wood has entirely absorbed the same, when it is to be removed, and is 'ready for use, i

My process is equally applicable to the treatment of wood for arresting its decay for a great lengt-h of time for the Avarious purposes of building bridges, wharves,'&`o., for railway-ties, pavements, and for a multitude of uses which it is not considered herein necessary to enumerate, or for preparing wood for innumerable applications in the tine arts.

Claims.

l. ,The process herein described, for treating wood for various useful or ornamental purposes.

2. Au apparatus for treating wood by impreguating. its pores and cellular' structure with various agents, so constructed or provided and operating a'sto be enabled to vary and determine the amount of impregna ting materials injected into the wood, for the purpose hereinbefore stated.

IRA HAYFORD.

Witnesses 

